2001 - of the Belgian Mathematical Society

Belgian Mathematical Society
Comité National de Mathématique
CNM
CWM
N
NCW
Nationaal Comité voor Wiskunde
BMS-NCM NEWS: the newsletter of the
Belgian Mathematical Society and the
National Committee for Mathematics
Campus Plaine c.p. 218/01,
Bld du Triomphe, B–1050 Brussels, Belgium
Tel.
(32)(2) 650.58.54
Fax
(32)(2) 650.58.67
E-mail
[email protected]
Website
http://www.ulb.ac.be/assoc/bms
BMS-NCM NEWS
—
No 32, March 15, 2001
Our colleague Pascal Laubin died on February 21st; he was 42 years old.
He had just been promoted Professeur ordinaire at the University of Liège.
He was an active member of the Committee of the Belgian Mathematical Society since 1992
and a member of the Editorial Board of the Bulletin of the Belgium Mathematical Society
- Simon Stevin.
Partial differential equations were his main field of interest and he was already well known
for his results.
We loose a brilliant mathematician, a clever and kind colleague, a friend.
The Belgian Mathematical Society presents its condolences to his relatives and assures
Françoise of its heartfelt sympathy.
News from the BMS
The Bulletin indexed in the Science Citation Index Expanded
The Editorial Board of the Bulletin proudly announces that the Bulletin of the Belg. Math. Soc. - Simon
Stevin has been given, for the year 1999, an impact factor of 0.346 in the ISI Science Citation Index Expanded.
With this remarkable result, the Bulletin ranks 76th in a list of 145 mathematical journals.
Membership
At the time of this writing, 22 new members joined the BMS. The BMS Committee is pleased to welcome:
BMS-NCM NEWS
#32, March 15, 2001
Bernou Jean-Louis (Fresnes, France)
Crama Yves (ULg)
Delhez Eric (ULg)
Dispa Sophie (ULg)
Gilson Olivier (ULg)
Lefebvre Michel (Lille, France)
Stiénon Mathieu (ULB)
Zhang Yinhuo (UIA)
2
Caubergh Magdalena (LUC)
Daili Noureddine (Sétif, France)
De Maesschalk P (LUC)
Elskens Yves (Univ. de Provence, Marseille)
Glineur François (FPMS)
Rigo Michel (ULg)
Stulens Koen
Chareyre Sébastien (Noisiel, France)
Dehaye Paul-Olivier (ULB)
Devillers Alice (ULB)
Fiorini Samuel (ULB)
Govaerts Patrick (RUG)
Roisin Jean-Roger(UCL)
Van Camp Ellen (KULeuven)
At the time of this writing also, 99 members have not yet renewed their membership for 2001; they are
kindly asked to pay their dues as soon as possible.
For details on membership fees and reciprocity agreements see Issue #31 of BMS-NCM NEWS (January 15,
2001) or the site http://www.ulb.ac.be/assoc/bms/bms.org.html#dues
2001 BMS-DMV Meeting
FIRST JOINT MEETING OF THE BELGIAN (BMS)
AND GERMAN (DMV) MATHEMATICAL SOCIETIES
LAST MINUTE INFORMATION
The FINAL deadline for the submission of abstracts is MARCH 31, 2001.
The reduced registration fee still applies until MARCH 16, 2001.
For detailed information on the meeting see:
• Issue #31 of BMS-NCM NEWS (January 15, 2001)
• The homepages:
http://math-www.uni-paderborn.de/Liege2001/
http://www.ulg.ac.be/sectmath/DMVSMBMain.html
which will be updated from time to time and which will contain some useful links.
LOCAL ORGANIZING COMMITTEE:
F. Bastin, J. Schmets (both Univ. Liège).
We look forward to seeing you at the meeting in Liège.
For the BMS and the DMV:
Klaus D. Bierstedt, Jean Schmets
Doctoral courses in the Flemish Universities
In the frame of a series of doctoral courses on mathematics organized by the Flemish universities a course on
Algebraic Topological Methods in Dynamical Systems will be organized during the second semester of
the academic year 2000-2001. The program of this course is as follows:
1 Thursday March 22, 2001, 14h30-16h30
A. Vanderbauwhede: Introduction to Dynamical Systems
During this introductory lecture a number of concepts from the theory of dynamical systems (such as limit
sets, invariant manifolds, hyperbolicity, etc.) , needed for the main courses (see (2)), will be introduced.
Place: Room 36, Galglaan 2, 9000 Gent (see http://cage.rug.ac.be/foto/map.html)
2 April 2-6, 2001, LUC Diepenbeek
Intensive Course Week, with the following courses:
- Konstantin Mischaikov (Georgia Institute of Technology): Conley Index Theory and Rigorous Computations
BMS-NCM NEWS
#32, March 15, 2001
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- Stefano Luzzatto (Imperial College): From Invariant Manifolds to Invariant Measures For further
information: see http://www.luc.ac.be/dysy/course
3 Monday Juni 11, 2001, Galglaan 2, 9000 Gent
Dynamical Systems Day
Speakers: Floris Takens (Groningen), Bernold Fiedler (Berlin), Robert Roussarie (Dijon)
The detailed schedule and the titles of the lectures will be announced later. This day will be organized
with the support of the Onderzoeksgemeenschap FWO Fundamentele Methoden en Technieken in
de Wiskunde.
4 There is a possibility that the foregoing activities will be complemented by a lecture of Matthias Kawski
(Arizona State University) on the use of computer algebra and multimedia techniques in the study of
dynamical systems; this lecture will be organised by Ivan Cnop at the VUB.
For further information please contact
André Vanderbauwhede: [email protected]
Freddy Dumortier: [email protected]
Séminaire interuniversitaire de logique mathématique
The DEA course (11.00 - 12.30) and the seminars (14.30 - 16.00) take place at the ULB, Campus Plaine, Bldg
NO, room 2NO906
The next DEA lecture will be given by Françoise Point (UMH), on March 22, 2001 at 11.00.
The following afternoon seminars are:
March 22, 2001, 14.30 Didier Misercque (Institut Meurice): Problèmes de mariages
April 26, 2001, 14.30 Diderik Batens (RUG): Extending the Realm of Logic. The Adaptive Logic Programme.
Note also:
Journée de Mathématique et de Sciences à Mons
March 29, 2001
Expositions de Posters et sculptures mathématiques dans la cour du “Pentagone”
organisé dans le cadre du Printemps des Sciences
The programme of the Seminar is regularly updated at
http://www.umh.ac.be/math/logic/seminars.htm
The Scientific Works of Charles-Jean de La Vallée Poussin
The first volume of the complete works of Charles-Jean de La Vallée Poussin has just been published, a co-edition
of the Académie Royale de Belgique and the Circolo Matematico di Palermo. Its exact title is
“Charles-Jean de La Vallée Poussin.- Collected Works - Oeuvres scientifiques - vol. I - Biography and
Number Theory - Biographie et théorie des nombres”
The scientific editors are Paul J. Butzer (Aachen), Jean Mawhin (Louvain-la-Neuve) and Pascale Vetro
(Palermo). The volume is devoted to the biography of de La Vallée Poussin and his work in number theory.
The biographical part contains the following contributions :
• P. Butzer and J. Mawhin : A biography of Charles-Jean de La Vallée Poussin
• Ch. A. de La Vallée Poussin : Charles-Jean de La Vallée Poussin : l’homme, sa vie et sa pensée
• J. Mawhin : The mathematical environment of Charles-Jean de La Vallée Poussin at the Université
Catholique de Louvain
BMS-NCM NEWS
#32, March 15, 2001
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• P. Butzer and J. Mawhin : Charles-Jean de La Vallée Poussin and the Académie Royale de Belgique
• P. Nastasi : Some remarks on the connections between Charles de La Vallée Poussin (and Landau and
Lebesgue) and Italian scientific and academic institutions
• P. Montel : Notice nécrologique sur Ch.-J. de La Vallée Poussin
• G. Lemaı̂tre : Charles Jean de La Vallée Poussin
• J.C. Burkill : Charles-J. de La Vallée Poussin
• J. Favard : Hommage à Charles de La Vallée Poussin
• Ch.J. de La Vallée Poussin : Complete list of publications
The part devoted to number theory contains the following two introductions
• T.M. Apostol : Contributions by Charles-Jean de La Vallée Poussin to the theory of numbers
• J. Mawhin : A note of de La Vallée Poussin on the prime number theorem in a publication of von
Mangoldt,
followed by all de La Vallée Poussin’s papers devoted to the theory of numbers, and in particular to the prime
number theorem.
The next three volumes will respectively contain the contributions of de La Vallée Poussin to
• Integration, Fourier series and differential equations
• Approximation theory
• Conformal mappings, potential theory and complex functions,
together with presentations by experts in the fields.
The price of Volume 1 is 100.000 Italian lires (Euro 52). It must be ordered at the following address : Circolo
Matematico di Palermo Via Archirafi 34 90123 Palermo Italy
FNRS Contact Group at the UCL and ULB
The traditional meeting Analyse Non Linéaire will take place
on Friday March 30, 2001
at the UCL in the morning (Institut de Mathématique, Chemin du Cyclotron 2, room Cycl 05) and
at the ULB in the afternoon (Campus Plaine, room 2NO906, 9th floor, Bldg NO)
Tentative Programme
09.30-10.30: Bernard Kawhohl (Univ. Kőln, Germany): Symmetry questions in PDE.
11.00-12.00: Gunther Lumer (UMH): Transformée de Laplace, EDP’s et aspect de la théorie du contrôle.
14.30-15.30: Philippe Clément (Univ. Delft, The Netherlands): Existence, a priori estimates and symmetry properties of positive solutions to p-Laplace systems.
16.00-17.00: Isaberlle Catto (CEREMADE, Univ. Paris-Dauphine): A Hartree-type variational problem for
crystals.
Lunch, offered by the FNRS, will be served at the ULB. If you plan to attend it, please inform J.-P. Gossez
(e-mail: [email protected]) before March 28, 2001.
The meeting is organized in the scope of the Contact Group Équations aux Dérivées Partielles et SemiGroupes
J.-P. GOSSEZ
E. LAMI-DOZO
J. MAWHIN
M. WILLEM
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#32, March 15, 2001
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PhD. Thesis at the ULB
Author: AZIZIEH Kadija
Title: A priori estimates, continuation methods and existence results for positive solutions of p-Laplace equations and systems
Place: Campus Plaine, Bldg NO, 9th floor, room 2NO906
Date: March 29, 2001
Time: 16.00
Abstract
Our purpose in this thesis is to establish some existence results, a priori estimates as well as symmetry
results for nonlinear elliptic partial differential equations involving the p-Laplacian operator. This operator,
defined by ∆p , is defined for 1 < p < ∞ by the following:
0
∆p : W01,p (Ω) → W −1,p (Ω) : u → div(|∇u|p−2 ∇u)
where Ω is a bounded domain of RN , N ≥ 1. This quasilinear operator becomes the usual Laplacian ∆ =
PN
∂2
i=1 (∂xi )2 if p = 2. It appears in some physical and mechanical problems, such as in glaciology or in fluid
mechanics, in the study of nonnewtonian fluids. It also appears in the context of Sobolev spaces as the derivative
of the Sobolev norm.
In the first chapter, we consider the problem:
−∆p u = f (u) in Ω
u=0
on ∂Ω
(1)
where 1 < p ≤ 2, Ω is a bounded convex domain of class C 2 and f : R → [0, +∞) is continuous on [0, +∞) and
locally Lipschitz continuous on (0, +∞) and satisfies
∃C0 , C1 > 0 such that C0 |u|q ≤ f (u) ≤ C1 |u|q
∀u ∈ R+
(2)
where q > p − 1. We prove the existence of a nontrivial positive solution for (1) by using a continuation method
and by establishing a priori L∞ estimates. These estimates are obtained by using a blow-up technique as well
as the moving hyperplanes method.
In the second chapter, we obtain partial results concerning nonvariational problems of the type:
−∆p u + ~b.∇u = f (u) in Ω
u=0
on ∂Ω
(3)
where ~b ∈ C 1 (Ω) avec div(~b) ≤ 0 and f : R → [0, +∞) is a continuous function satisfying (2) with q >
max{p − 1, 1/(p − 1)} if ~b 6= 0. We extend for this purpose some properties of the p-Laplacian to the operator
−∆p + ~b.∇.
In the third chapter, we prove the existence of a nontrivial positive solution for the system
−∆p1 u = f (v) in Ω, u = 0 on ∂Ω
−∆p1 v = g(u) in Ω, v = 0 on ∂Ω
(4)
where p1 , p2 ∈ (1, 2) or p1 > 1, p2 = 2, and where f, g : R → R+ are continuous on [0, +∞) and locally Lipschitz
continuous on (0, +∞) and nondecreasing functions satisfying
C1 |s|q1 ≤ f (s) ≤ C2 |s|q1 ,
D1 |s|q2 ≤ g(s) ≤ D2 |s|q2
∀s ∈ R+
for some constants C1 , C2 , D1 , D2 > 0 and q1 q2 > (p1 − 1)(p2 − 1). We use as in the first chapter a contiuation
method and we obtain a priori estimates by blow-up. To apply this last technique, we prove by using the moving
hyperplane method some symmetry result for (4), result allowing us to locate the global maxima of u and v.
BMS-NCM NEWS
#32, March 15, 2001
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Vacancy for a mathematician at the VUB
Vacature Nummer : WE / 2001 / 005
Faculteit : Wetenschappen
Betrekking : Zelfstandig Academisch Personeel
Intern of Extern : Extern
Mandaat : Voltijds Zelfstandig Academisch Personeel
Ingangsdatum : 01/10/2001
Vakgebied : Wiskunde
Omschrijving :
a) Onderwijs :
– Onderwijs op kandidatuursniveau (90 HOC + 90 WPO) betreffende lineaire algebra, analytische
meetkunde, analyse, gericht tot niet wiskundigen uit opleidingen behorende tot de exacte -en toegepaste
wetenschappen.
– Hogere analyse (30 HOC + 15 WPO), 2e lic.
– Wiskunde Keuzevakken aansluitend bij het onderzoek (60 HOC), 1e en 2e lic.Wiskunde
b) Wetenschappelijk onderzoek : Onderzoek in een domein van de wiskunde gericht naar de Analyse
Vereisten : diploma doctor in de wetenschappen (wiskunde) of van geaggregeerde hoger onderwijs
Contactpersoon : Prof. Dr. E. Colebunders, Contact Telefoon : 02/629 3486 - Secr. 02/629 3471
Contact E-mail : [email protected]
Naam Decaan : Prof. Dr. J. Lemonne
Inwachtingstermijn : 1 maand na publicatie in het Belgisch Staatsblad
Publicatiedatum Belgisch Staatsblad : 29/02/2001
De kandidaten worden verzocht gebruik te maken van het daartoe bestemde kandidaatstellingsformulier met
verklaring vrij onderzoek en cumulatieformulier dat kan gedownload worden op het internetadres
http://www.vub.ac.be/DP/AP.html
of bekomen worden op de Dienst Personeel (tel. 02/629.20.02) van de Vrije Universiteit Brussel, Pleinlaan 2 te
1050 Brussel.
En ingevuld kandidaatstellingsformulier dient gericht te worden aan de Rector van de Vrije Universiteit
Brussel. En kopie van het kandidaatstellingsformulier dient gelijktijdig gericht te worden aan de Decaan van de
Faculteit.
Art et Mathématique ou la rencontre de deux univers
The Musée des sciences et des techniques de Parentville and the Musée des Beaux-Arts de Charleroi jointly
organize, from February 9 till June 3, 2001 the following exhibitions:
• At the Musée des sciences et techniques de Parentville:
Maths 2000 an exhibition of the ”Cité des Sciences et de l’Industrie - La Vilette (Paris)
Symétries du monde. Rencontre de la géométrie, de l’art et de l’anthropologie, an exhibition organized by the students in Social Sciences of the U. L. B.
• At the Musée des Beaux-Arts de Charleroi: Méthode et Langage
As a complement to the exhibitions, the two museums also organize conferences (in French):
• At the Musée des sciences et techniques de Parentville:
March 2 2, 2001, 14.00 Luc Lemaire (ULB): La Recherche en mathématique
March 27, 2001, 14.00 Michel Demal (UREM-ULB, GEPEMA-HMH, HECF-Mons): Les polyèdres à
faces non planes
March 29, 2001, 14.00 Christine De Mol (ULB) Mathématique, son et image
April 24, 2001, 14.00 Jean-Paul Doignon (ULB) Mathématique et cinéma
BMS-NCM NEWS
#32, March 15, 2001
• At the Musée des Beaux-Arts de Charleroi:
May 3, 2001, 10.00 and 14.00 Marc Feulien (artist) :Le carré, le cube et la matière.
For further information and reservations
Musée des Beux-Arts de Charleroi
Hôtel de Ville - 2e étage
Place Charles II
B-6000 Charleroi
Musée des sciences et techniques de Parentville
Université de Bruxelles
Rue de Villers 227
B-6010 Charleroi (Couiilet)
Tel: +32 71/86 11 36 or 34
Fax: +32 71/86 11 33
e-mail: [email protected]
+32 71/60 03 00
+32 71/60 03 05
e-mail: [email protected]
See also http://www.ulb.ac.be/musees/parentville/
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